The background image for your device, also known as the wallpaper, can be changed in settings. You can use your own image as a wallpaper or choose from the default images on your device. You can change the lock screen and home screen backgrounds.
From the Home screen, tap Settings.
Scroll to Wallpaper.
Tap Choose a New Wallpaper.
Note: For this tutorial, we're selecting static wallpapers. Dynamic wallpapers move on their own and add motion to your Home screen. You can also select one of your own images from the Photos app.